Atmospheric or power hammer



J. SLEE.

ATMOSPHERIC 0R POWER HAMMER.

APPLICATION FILED MAY 6, I915.

Patented Dec. 21, 1920..

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ATMOSPHERIC 0R POWER HAMMER.

APPLICATION FILED MAY 6, i915. 1,363,0%1 Patented Dec. 21, 1920.

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JOHN SLEE, 0F NEWTON-LE-WT-LLOWS, ENGLAND, ASSIGNOE OF THIRTY ONE-HUNDREDTHE TO ROBERT EDW'ARD BTIBBY TREVOR, O1? LIVERPOOL, ENG- LAND,AND THIRTY ONE-I-UJ'NDREDTHS T0 HERBERT WILLIAM JOHNSON,

OF ST. HELENS, ENGLAND.

ATMOSPHERIC OR POWER HAMMER.

Application filed May 6,

T 0 (all whom it may concern:

Be it known that I, JOHN SLIDE, a subject of the King of Great Britain,residing at Newton-le-lVillo'ws, in the county of Lancaster, in theKingdom of England, have invented certain new and useful Tmprovements inor Relating to Atmospheric or Power Hammers, of which the following is aspecification.

The present invention relates to improvements in atmospheric or powerhammers in which an air cushion is interposed between the driving memberand the hammer member. This air cushion is formed of a piston andcylinder, one member of which is connected to the driving mechanismwhile the other is connected to the hammer or head member. Energy willbe stored at certain portions of the cycle in the cushion of air betweenthe piston and the cylinder and this energy will later in the cycle beimparted to the hammer.

According to the arrangement, the cylinder is arranged to reciprocatetoward and away from the anvil block, and the hammer head (or a pistonor plunger attached to the hammer head) is arranged to work in thecylinder. As the cylinder descends, the air above the piston iscompressed, and is stored up to deliver the downward blow, the strengthof which is dependent upon the force of the compressed air. As the cylind r ascends, air enters through holes in the cylinder and air below thepiston is compressed and the hammer head is lifted. We are by this meansable to provide a pneumatic hammer in which the use of a storagereservoir charged with compressed air by means of an air compressingpump, is dispensed with.

The invention is more particularly described with reference to theaccompanying drawings, in which Figure 1 is a side elevation of animproved power hammer.

Fig. 2 is a corresponding plan View.

Fig. 3 is a view of a detail.

Fig. 4 is a corresponding plan view to Fig. 3.

The power hammer l in a preferred form of construction (Fig. l) ismounted direct on to the piston rod 2 of piston working in cylinder 3.This cylinder 3 carries Specification of Letters Patent.

Patented Dec. 21, 192@.

1915. Serial No. 26,264.

trunnions a by which it is connected bv means of links 5 to a cross beam6 pivoted at or near its middle on the spindle 7. The beam 6 at itsopposite end is connected by links (not shown) to a crank on theoperatng shaft of the machine. The cylinder 3 is mounted to be slidablein guides 8 on the frame 9. The hammer l cooperates with a fixedblock-10 in the usual manner. In the cylinder 3 a piston 11 is arrangedto recip rocate. It will be seen therefore, that the motion of thecylinder 3 on the guides 8 and of the hammer head 1 is controlled fromthe beam 6, but an elastic cushion is arranged between the cylinder 3and the hammer 1.

The stuiiing box for the piston rod preferably acts as means forpreventing the piston rotating relatively to the cylinder. As shown thepiston rod let is flattened on two sides and cheeks 18 bear againstthese fiattened sides to act as guide members and as a packing means forthe rod 14. These cheeks 18 are adjustable by means of set screws or thelike 19*". The members 18 may carry as shown, the valves 15 leading tothe atmosphere.

The cylinder 3 is double-acting and the piston rod carries a piston 11.An automatic air valve such as 20 is provided to control air inlet toone end of the cylinder which can be further provided with perforations17 for determining the point at which compression commences.

A crank member 48 carries a connecting rod 59 on which are threadedpistons 60 working in cylinders 61 connected to the end 62 of the beam6. air inlet means controlled either by the passage of the pistons inthe cylinder members or by automatic valves may be provided in thecylinders 61 and air inlet valves are provided in the pistons 60themselves. To regulate the degree of compression in the cylinders 61the pistons 60 may be displaced along the piston rods 59 by turning themrelatively thereto and they can be locked in any desired adjustedpositions by means of the lock nuts 63.

It is obvious that a considerable control over the acceleration of thehammer 1 during the cycle of rotation of the crank 48 can be exercisedby differential adjustment of the pistons60 relatively to one anotherand the piston rod 59. Such differential adjustment can be furtherexercised as previously piston carrying the hammer head behind thedefinitely controlled member, for instance, the positively operatedcylinder, may be adjusted to be difierent on the upstroke than 011 thedownstroke.

When the apparatus is at rest, the cylinder contains air at atmosphericpressure, which air has free access thereinto by the holes or ports atmidlength. If now the shaft be set into motion, the cylinder will bereciprocated up and down toward and away from the anvil block. As thecylinder descends the air above the piston is compressed and is storedup to give the hammer head its downward blow, the strength of the blowbeing dependent upon the force of the compressed air. Instant expansionof the air above the piston takes place when the crank and connectingrod turn the bottom center, and the cylinder begins to ascend. As thecylinder ascends, the air below the piston is compressed, and a hammerhead is lifted. On the cylinder commencing its next descent, the pistonwill pass above the ports or holes, thus imprisoning air at the top ofthe cylinder to give the hammer head its downward blow, while on itsascent the piston will pass below the ports or holes, thus allowing afresh supply of air to rush in into the upper part of the cylinder forthe next compression. By this means the necessary body of air above thepiston is replenished at each stroke. This alternate action ofcompressing the air above and below the piston will continue until therotation of the shaft is stopped. In order to produce a succession ofblows, the power shaft is set in continuous motion, or when the shaft isstopped the blows will cease, the hammer head remaining in the raised orlowered position according to the position of the rocking beam.

The hammer thus makes a number of blows equal to the revolutions of therotary shaft, and the force of the blows is regulated by regulating thespeed of the shaft, and also by regulating by means of the disks,

the position to which the hammer head is allowed to descend, that is tosay the farther the hammer head descends the stronger will be the blowdelivered. The cylinder alone has operating connections while the pistontherein is wholly an atmospheric actuated piston, governed in all itsmovements by the atmosphere within the cylinder, and by thereciprocation of the cylinder.

The term cylinder as used herein, is used to define the chamber whereinthe piston works, and must be understood to be comprehensive enough tocover any chamber in which a piston will reciprocate. Furthermore, theterms downward and upward are used herein to define the forward strokeof the piston and cylinder, and their return stroke, which need not ofcourse be necessarily up and down in a vertical direction.

I declare that what I claim is 1. A power hammer comprising a frame, acrank shaft journaled therein, a beam pivoted on said frame, a valvedair cylinder connected to one end of said beam, a piston operable insaid cylinder, a rod connecting said piston and said crank, theconnection between said rod and piston being adjustable for varying thecompression in said air cylinder, acylinder connected to the other endof said beam and reciprocable on said frame, a free piston operable insaid cylinder, a hammer connected to said piston, and means for causingthe reciprocation of said cylinder to operate said piston to ac tuatethe hammer.

2. An atmospheric or power hammer, comprising a frame, a main shaftjournaled in said frame, a crank on said main shaft, a beam pivoted onsaid frame, a connecting rod connected to said crank, a pneumaticcylinder connected to the beam, a piston moving in said cylinder andconnected to one part of the connecting rod, means whereby said pistonmay be adjusted relatively to said rod, a hammer, and a free piston andcylinder connection between said hammer and the opposite end of saidbeam.

In witness whereof,I have hereunto signed my name this 23 day of April,1915, in the presence of two subscribing witnesses.

JOHN SLEE.

Witnesses:

HAROLD E. Por'rs, ROBERT E. B. Tnoon.

